The subject matter of the invention are moulded articles with leather-like surfaces for use in the automobile industry as well as a process for the production thereof.
The use of waste leather is known from "Ullmanns Encyklopadie der technischen Chemie", 4. ed., vol. 16, p. 174. According to this, waste leather can be defibrated and subsequently can be processed to fibrous waste leather. By this single-layered sheet materials of leather fibers and binders are understood. According to this, the fibrous leather materials are used for bag leather goods, but particularly in the production of shoes as well as for technical leather gaskets. The waste leather materials are, for instance, wet or dry ground in crushing mills, or wet ground in toothed disk mills and refiners, or also wet defibrated in hollander beaters, whereby the fibers should have a length of 3 to 12 mm. Water insoluble, particularly natural or synthetic rubber latices as well as dispersions of acrylic ester, vinylester and isobutylene polymerizate and mixed polymerizates have been found to be particularly successful as binders. The amount of binder is between 8 and 40%. With fibrous leather materials having higher portions (20 to 30%) of water insoluble binders, the characteristics of the binder are according to this preponderating. With goods having a lower content of binder (less than 20%), the fibrous character is preponderating; these materials are more absorptive and more leather-like.
From DE 34 17 369 C2 a process is known for producing an injection-mouldable compound material in which a polyester-cotton mixed fiber from waste fabric is fused with a polyolefin. However, the material prepared in this way does not have a sufficient water-absorbing capacity, as well as the feel characteristics, typical of leather.
DE 21 20 149 A1 describes weather resistant and torsion-free plates, tubes, rods and other moulded articles consisting of binders and filler made of used material, among other things waste of paper, cardboard articles, knitted goods, cottons, linens, synthetic fibers, leather, rags, hay, straw, foliage, grass, shells of cereals and fruits, pits and peels of fruits and potatoes as well as metal chips, metal grains, metal powders, metals, polystyrene, waste from plastic processing, natural fibers like jute, sisal or hemp. Information about the amounts of used filler materials is not included.